Re: [f2fs-dev] [PATCH] f2fs: fix to migrate all curseg types during free_segment_range

[Chao Yu <chao@kernel.org>]

On 8/19/26 01:00, Daeho Jeong wrote:
> From: Daeho Jeong <daehojeong@google.com>
> 
> In free_segment_range(), the curseg evacuation loop only iterates up to
> NR_CURSEG_PERSIST_TYPE (0..5), missing non-persistent in-memory curseg
> types such as CURSEG_COLD_DATA_PINNED and CURSEG_ALL_DATA_ATGC.
> 
> Even though these in-memory curseg types are not saved in the on-disk
> checkpoint header, they still occupy active physical segments at runtime.
> If an active in-memory curseg happens to be allocated within the segment
> range being truncated during filesystem shrink, failing to evacuate it
> will cause subsequent writes to the curseg attempting out-of-bounds I/O
> on the truncated storage range.
> 
> Fix this by expanding the curseg evacuation loop upper bound to
> NR_CURSEG_TYPE to ensure all active curseg types are safely migrated
> out of the target range.
> 

Need fixes and Cc stable line.

> Signed-off-by: Daeho Jeong <daehojeong@google.com>
> Signed-off-by: Sunmin Jeong <s_min.jeong@samsung.com>
> ---
>  fs/f2fs/gc.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
> index ffaa7ba76a1b..192b16ac02f8 100644
> --- a/fs/f2fs/gc.c
> +++ b/fs/f2fs/gc.c
> @@ -2222,7 +2222,7 @@ static int free_segment_range(struct f2fs_sb_info *sbi,
>  	mutex_unlock(&DIRTY_I(sbi)->seglist_lock);
>  
>  	/* Move out cursegs from the target range */
> -	for (type = CURSEG_HOT_DATA; type < NR_CURSEG_PERSIST_TYPE; type++) {
> +	for (type = CURSEG_HOT_DATA; type < NR_CURSEG_TYPE; type++) {
>  		err = f2fs_allocate_segment_for_resize(sbi, type, start, end);
>  		if (err)
>  			goto out;